To protect private content of a user in a terminal, a terminal screen is usually locked to improve terminal usage security for the user in the prior art. A fixed numeric password is usually used to unlock the terminal screen. That is, when the terminal screen needs to be unlocked, the user enters the fixed numeric password by tapping the screen to unlock the terminal screen, so that the user can completely control the terminal, including permission for the user to access private content of an owner in the terminal.
Because the fixed digital number used to unlock the terminal screen is easy to leak, the solution of using the fixed numeric password to unlock the terminal screen cannot completely protect terminal usage security for the user.